1. Field of the Invention
The present invention relates to a device for use in various types of immunoassays, and particularly to a precision cutting instrument for slicing solid support sheets used in preparing immunoassay strips.
2. Brief Description of Prior Art
Recent advances in basic research techniques have produced highly sensitive diagnostic assays which are rapidly being refined for widespread use in hospitals, blood banks, and commercial laboratories. One such technique, commonly known as Western Blot analysis, is described in U.S. Pat. No. 4,452,991. By this technique, proteins which have been separated or otherwise dispersed in a gel are electrophoretically transferred to and immobilized upon solid support sheets, such as nitrocellulose sheets. Generally, when Western Blot analysis is used as a diagnostic tool, the solid support sheets are cut into strips which are then further treated and/or exposed to the sample to be tested.
Of particular significance is the use of Western Blot analysis to detect the presence in human serum of antibodies against a variety of disease related antigens. A commercial kit for detecting the presence of a particular antibody would necessarily contain strips of the solid support sheets to which proteins or antigens have been electrophoretically transferred. Currently, due to the delicate nature of the solid support sheets and the proteins immobilized thereon, the solid support sheets are cut into strips by hand using a sharp razor blade or similar tool. While this method of cutting solid support sheets is suitable for most basic research procedures requiring a relatively small number of strips, the commercial production of diagnostic test kits requires a means for rapidly and accurately slicing the solid support sheets to produce large volumes of identical strips which provide reliable and readily reproduced results.
Although many types of cutting devices are known in the prior art, none of these devices are suitable for use with the delicate materials required in current immunological technology. For instance, U.S. Pat. No. 2,409,203 discloses a device for slitting sheets of cellulosic or plastic film to enable the strips produced to be subjected to tests of elongation and tensile strength. However, the cellulosic material is secured to the device by tightening a clamp over each end of the material. Such clamps would be unsuitable for securing the delicate solid support sheets utilized in most immunoassays.
Thus, a need exists for a precision cutting instrument which can rapidly and accurately slice solid support sheets upon which proteins have been immobilized into strips which are suitable for use in the commercial production of diagnostic test kits.